Engineered biomaterials to mitigate growth factor cost in cell biomanufacturing

What Technological and Economic Elements Must be Addressed to Support the Affordability, Accessibility, and Desirability of Alternative Proteins in LMIC?

Populations in low- and middle-income countries (LMIC) typically consume less than the recommended daily amount of protein. Alternative protein (AP) sources could help combat malnutrition, but this requires careful consideration of elements needed to further establish AP products in LMIC. Key considerations include technological, nutritional, safety, social, and economic challenges. This perspective analyzes these considerations in achieving dietary diversity in LMIC, using a combination of traditional and novel protein sources with high nutritional value, namely, soy, mycoprotein, and cultivated meat. Technological approaches to modulate the technofunctionality and bitter off-tastes of plant-sourced proteins facilitate processing and ensure consumer acceptance. Economic considerations for inputs, infrastructure for production, and transportation represent key elements to scale up AP. Dietary diversification is indispensable and LMIC cannot rely on plant proteins alone to provide adequate protein intake sustainably. Investments in infrastructure and innovation are urgently needed to offer diverse sources of protein in LMIC.

Cultured Meat Safety Research Priorities: Regulatory and Governmental Perspectives

As with every new technology, safety demonstration is a critical component of bringing products to market and gaining public acceptance for cultured meat and seafood. This manuscript develops research priorities from the findings of a series of interviews and workshops with governmental scientists and regulators from food safety agencies in fifteen jurisdictions globally. The interviews and workshops aimed to identify the key safety questions and priority areas of research. Participants raised questions about which aspects of cultured meat and seafood production are novel, and the implications of the paucity of public information on the topic. Novel parameters and targets may require the development of new analytical methods or adaptation and validation of existing ones, including for a diversity of product types and processes. Participants emphasized that data sharing of these efforts would be valuable, similar to those already developed and used in the food and pharmaceutical fields. Contributions to such databases from the private and public sectors would speed general understanding as well as efforts to make evaluations more efficient. In turn, these resources, combined with transparent risk assessment, will be critical elements of building consumer trust in cultured meat and seafood products.

A path to translation: How 3D patient tumor avatars enable next generation precision oncology

3D patient tumor avatars (3D-PTAs) hold promise for next-generation precision medicine. Here, we describe the benefits and challenges of 3D-PTA technologies and necessary future steps to realize their potential for clinical decision making. 3D-PTAs require standardization criteria and prospective trials to establish clinical benefits. Innovative trial designs that combine omics and 3D-PTA readouts may lead to more accurate clinical predictors, and an integrated platform that combines diagnostic and therapeutic development will accelerate new treatments for patients with refractory disease.

Recent advances in coiled-coil peptide materials and their biomedical applications

Extensive research has gone into deciphering the sequence requirements for peptides to fold into coiled-coils of varying oligomeric states. More recently, additional signals have been introduced within coiled-coils to promote higher order assembly into biomaterials with a rich distribution of morphologies. Herein we describe these strategies for association of coiled-coil building blocks and biomedical applications. With many of the systems described herein having proven use in protein storage, cargo binding and delivery, three dimensional cell culturing and vaccine development, the future potential of coiled-coil materials to have significant biomedical impact is highly promising.

Supramolecular glycopolymers: How carbohydrates matter in structure, dynamics, and function

Supramolecular glycopolymers exhibiting inherent dynamicity, tunability, and adaptivity allow us to arrive at a deeper understanding of multivalent carbohydrate-carbohydrate interactions and carbohydrate-protein interactions, both being essential to key biological events. The impacts of the carbohydrate segments in these supramolecular glycopolymers towards their structure, dynamics, and function as biomaterials are addressed in this minireview. Bottlenecks and challenges are discussed, and we speculate about possible future directions.

Enhanced Bone Regeneration via PHA Scaffolds Coated with Polydopamine-Captured BMP2

The hierarchical three-dimensional (3D)-printing scaffolds based on microbial polyester poly(3-hydrxoybutyrate-co-4-hydroxybutyrate) (P34HB) were designed and used for bone tissue engineering via surface functionalization on the 3D-printed (P34HB) scaffolds using polydopamine (PDA)-mediated...

A poly(ethylene glycol) three-dimensional bone marrow hydrogel

Three-dimensional (3D) hydrogels made from synthetic polymers have emerged as in vitro cell culture platforms capable of representing the extracellular geometry, modulus, and water content of tissues in a tunable fashion. Hydrogels made from these otherwise non-bioactive polymers can be decorated with short peptides derived from proteins naturally found in tissues to support cell viability and direct phenotype. We identified two key limitations that limit the ability of this class of materials to recapitulate real tissue. First, these environments typically display between 1 and 3 bioactive peptides, which vastly underrepresents the diversity of proteins found in the extracellular matrix (ECM) of real tissues. Second, peptides chosen are ubiquitous in ECM and not derived from proteins found in specific tissues, per se. To overcome this critical limitation in hydrogel design and functionality, we developed an approach to incorporate the complex and specific protein signature of bone marrow into a poly (ethylene glycol) (PEG) hydrogel. This bone marrow hydrogel mimics the elasticity of marrow and has 20 bone marrow-specific and cell-instructive peptides. We propose this tissue-centric approach as the next generation of 3D hydrogel design for applications in tissue engineering and beyond.

Promises and Challenges of Organoid-Guided Precision Medicine

Organoids are self-organizing, expanding 3D cultures derived from stem cells. Using tissue derived from patients, these miniaturized models recapitulate various aspects of patient physiology and disease phenotypes including genetic profiles and drug sensitivities. As such, patient-derived organoid (PDO) platforms provide an unprecedented opportunity for improving preclinical drug discovery, clinical trial validation, and ultimately patient care. This article reviews the evolution and scope of organoid technology, highlights recent encouraging results using PDOs as potential patient "avatars" to predict drug response and outcomes, and discusses critical parameters for widespread clinical adoption. These include improvements in assay speed, reproducibility, standardization, and automation which are necessary to realize the translational potential of PDOs as clinical tools. The multiple entry points where PDOs may contribute valuable insights in drug discovery and lessen the risks associated with clinical trials are also discussed.

Heparin-mediated electrostatic immobilization of bFGF via functional polymer films for enhanced self-renewal of human neural stem cells

Preserving the self-renewal capability of undifferentiated human neural stem cells (hNSCs) is one of the crucial prerequisites for efficient hNSC-based regenerative medicine. Considering that basic fibroblast growth factor (bFGF) is one of the key contributing factors in maintaining the self-renewal property of hNSCs, the bioactivity and stability of bFGF in the hNSC culture should be regulated carefully. In this study, we developed a functional polymer film of poly(glycidyl methacrylate (GMA)-co-N,N-dimethylaminoethyl methacrylate (DMAEMA)) (coGD, or p(GMA-co-DMAEMA)) via initiated chemical vapor deposition (iCVD), which facilitated a stable, electrostatic adsorption of heparin and subsequent immobilization of bFGF. The bFGF-immobilized coGD surface substantially enhanced the proliferation rate and neurosphere forming ability of hNSCs compared to tissue culture plate (TCP). The expression of the stemness markers of hNSCs such as NESTIN and SOX-2 was also upregulated prominently on the coGD surface. Also, the hNSCs cultured on the coGD surface showed enhanced neurogenesis upon spontaneous differentiation. The immobilized bFGF on the coGD surface stimulated the expression of bFGF receptors and subsequently activated the mitogen-activated protein kinase (MAPK) pathway, attributed to the increase in self-renewal property of hNSCs. Our results indicate that the coGD surface allowed in situ heparin-mediated bFGF immobilization, which served as a robust platform to generate hNSC neurospheres with enhanced self-renewal and differentiation capabilities and thereby will prompt an advance in the field of therapeutics of neurodegenerative diseases.

Strategies to Control or Mimic Growth Factor Activity for Bone, Cartilage, and Osteochondral Tissue Engineering

Growth factors play a critical role in tissue repair and regeneration. However, their clinical success is limited by their low stability, short half-life, and rapid diffusion from the delivery site. Supraphysiological growth factor concentrations are often required to demonstrate efficacy but can lead to adverse reactions, such as inflammatory complications and increased cancer risk. These issues have motivated the development of delivery systems that enable sustained release and controlled presentation of growth factors. This review specifically focuses on bioconjugation strategies to enhance growth factor activity for bone, cartilage, and osteochondral applications. We describe approaches to localize growth factors using noncovalent and covalent methods, bind growth factors via peptides, and mimic growth factor function with mimetic peptide sequences. We also discuss emerging and future directions to control spatiotemporal growth factor delivery to improve functional tissue repair and regeneration.

Integrating biomaterials and food biopolymers for cultured meat production

Cultured meat has recently achieved mainstream prominence due to the emergence of societal and industrial interest. In contrast to animal-based production of traditional meat, the cultured meat approach entails laboratory cultivation of engineered muscle tissue. However, bioengineers have hitherto engineered tissues to fulfil biomedical endpoints, and have had limited experience in engineering muscle tissue for its post-mortem traits, which broadly govern consumer definitions of meat quality. Furthermore, existing tissue engineering approaches face fundamental challenges in technical feasibility and industrial scalability for cultured meat production. This review discusses how animal-based meat production variables influence meat properties at both the molecular and functional level, and whether current cultured meat approaches recapitulate these properties. In addition, this review considers how conventional meat producers employ exogenous biopolymer-based meat ingredients and processing techniques to mimic desirable meat properties in meat products. Finally, current biomaterial strategies for engineering muscle and adipose tissue are surveyed in the context of emerging constraints that pertain to cultured meat production, such as edibility, sustainability and scalability, and potential areas for integrating biomaterials and food biopolymer approaches to address these constraints are discussed. STATEMENT OF SIGNIFICANCE: Laboratory-grown or cultured meat has gained increasing interest from industry and the public, but currently faces significant impediment to market feasibility. This is due to fundamental knowledge gaps in producing realistic meat tissues via conventional tissue engineering approaches, as well as translational challenges in scaling up these approaches in an efficient, sustainable and high-volume manner. By defining the molecular basis for desirable meat quality attributes, such as taste and texture, and introducing the fundamental roles of food biopolymers in mimicking these properties in conventional meat products, this review aims to bridge the historically disparate fields of meat science and biomaterials engineering in order to inspire potentially synergistic strategies that address some of these challenges.

Synthetic alternatives to Matrigel

Matrigel, a basement-membrane matrix extracted from Engelbreth-Holm-Swarm mouse sarcomas, has been used for more than four decades for a myriad of cell culture applications. However, Matrigel is limited in its applicability to cellular biology, therapeutic cell manufacturing and drug discovery owing to its complex, ill-defined and variable composition. Variations in the mechanical and biochemical properties within a single batch of Matrigel - and between batches - have led to uncertainty in cell culture experiments and a lack of reproducibility. Moreover, Matrigel is not conducive to physical or biochemical manipulation, making it difficult to fine-tune the matrix to promote intended cell behaviours and achieve specific biological outcomes. Recent advances in synthetic scaffolds have led to the development of xenogenic-free, chemically defined, highly tunable and reproducible alternatives. In this Review, we assess the applications of Matrigel in cell culture, regenerative medicine and organoid assembly, detailing the limitations of Matrigel and highlighting synthetic scaffold alternatives that have shown equivalent or superior results. Additionally, we discuss the hurdles that are limiting a full transition from Matrigel to synthetic scaffolds and provide a brief perspective on the future directions of synthetic scaffolds for cell culture applications.

Development and Validation of a Virtual Gelatin Model Using Molecular Modeling Computational Tools

To successfully design and optimize the application of hydrogel matrices one has to effectively combine computational design tools with experimental methods. In this context, one of the most promising techniques is molecular modeling, which requires however accurate molecular models representing the investigated material. Although this method has been successfully used over the years for predicting the properties of polymers, its application to biopolymers, including gelatin, is limited. In this paper we provide a method for creating an atomistic representation of gelatin based on the modified FASTA codes of natural collagen. We show that the model created in this manner reproduces known experimental values of gelatin properties like density, glass-rubber transition temperature, WAXS profile and isobaric thermal expansion coefficient. We also present that molecular dynamics using the INTERFACE force field provides enough accuracy to track changes of density, fractional free volume and Hansen solubility coefficient over a narrow temperature regime (273-318 K) with 1 K accuracy. Thus we depict that using molecular dynamics one can predict properties of gelatin biopolymer as an efficient matrix for immobilization of various bioactive compounds, including enzymes.